Your new motor should be strong. The biggest restriction on your old motor was the heads. 305 heads may give more compression but just don't flow. The only change I'd make is to use a Performer RPM intake. I have the same basic setup up as your old motor but use stock 194/150 valve heads, 76 cc chambers and a Weiand Stealth. Its a strong runner and is very driveable and with the bigger cam in your new motor, and better heads you will have a strong runner. Torque may be a little weaker at lower rpm's but overall torque and hp will be higher